sdl2: add patch to fix busy-loop in C library

sdl2: add patch to fix busy-loop in C library

For some obscure reason, the order in which the libdrm/libgbm libraries
are loaded matters.

Without this fix, the first call to check_modesetting() will work and
load then unload all symbols properly, but the second call to this
function will lock up as soon as dlopen() is called on libdrm.

Swapping the order in which the libdrm and libgbm libraries are loaded
is enough to fix (or work around?) this issue.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
[yann.morin.1998@free.fr: add upstream commit URL]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>